valves/ bubbley idle

[GREASEMONKEY72]

do you think the valves needing to be adjusted could be the reason for the bubbly sound i have at idle?


and also what would cause a stumble when you hit the gas? like you go to floor it and it just goes bleh...then goes, and if it matters the other night i was rolling at about 25mph or so and i was tapping the throttle enough to make the truck lift up a bit multiple times and at one point it did a little backfire

(quadrajet on a stock 350)


TIA

[eedgell]

Sounds like carb to me. The stumble on take off is probably the accelerator pump. The rest could be carb as well. Go edelbrock and forget it.

[GREASEMONKEY72]

i want to keep the qjet and get it tuned right

anybody else have anymore input?


i did put in a new float not to long ago and when i put it back on the truck it was flooding out so i moved the accel pump shaft to the inner hole i believe and it idled perfectly and the float is set to spec and the secondaries dont always kick in like they used to when i get on it

[GREASEMONKEY72]

ttt

[6872xtc]

I have always liked Q-jets, not that I am knocking holley or edelbrock. I got mine built by SMI (Sean Murphy Induction) and I'm very pleased. I know that it's possible that you had something go wrong, but check threads in engine and drivetrain section, there are a couple of us with SMI carbs. I put rebuild kits in my own carbs for years but now have a lot of faith in SMI.

[Big D]

Put a Vacumn gauge on the motor, A fluttering needle will be the sign of a valve problem. I'm getting ready to tear apart the 350 out of my 72 C-20. It ran great but the vacumn would constantly jump from 16 to 18 pounds.

The stumble sounds like a carb problem, But it could be timing is off also.

[GREASEMONKEY72]

what should the vaccum be at?

the timming is set the same as before i put in the new float and yes i checked it and its at 8*btdc

would the valves needing to be adjusted affect it?

[corn]

Im guessing carb... Are the lifters ticking a lot? If not, I doubt adjusting will help any... Trying a Seafoam treatment couldnt hurt.

[GREASEMONKEY72]

i found the problem, the right barrel squiter isnt squirting, that would explain the stumble but i took the carb off and cleaned it all out and put it back on and fired it up and its still not squirting, anybody know why it wouldnt be squirting when everything was clean when i pulled it apart and sprayed through the tubes and holes and everything?????

[sodak69c10]

its been a while since i worked on a quadrajunk but lets see, are you just spraying threw the holes with acan up carb clean or are you using compressed air to blow threw the holes,(careful you can blow a needle threw the float on some carbs, that was a bad day) did you rebuild the entire carb or just put the float in(is the float set right?) might not hurt to disassemble entirely soak in dunk bascket then blow all passages out and install new gaskets, and accelerator pump diaphram.

[GREASEMONKEY72]

it was a can of carb clean but it came out just fine and i rebuilt the carb about 8 months ago and about 2 months ago i put in the new float, i can pull it all back apart tomorrow and blow it out with air, the gasket on the accel pump is fine, theres no tears or holes in it, i just dont get it, unless theres a tiny piece of dirt in there thats stoping it from squirting with the accel pump

[GREASEMONKEY72]

i pulled it apart again, took the jets out, sprayed it all out with carb clean then blew it all out with the compresser, put it back together and pumped it by hand on the bench and only had air coming out of the one side still, so i pulled it back apart and took the bottom plate off to this time and sprayed it all out but i havnt put it back together yet to try it

the gasket on the accel pump is fine

is there anything else i should be looking for?

she is my only vehicle so the sooner i can get this fixed the better

[GREASEMONKEY72]

well i just put the bottom plate back on and tried it and its still not working, what could it be?

[eedgell]

It has been a while on the Q-jet for me, but when cleaning them you must be very thorough. All three parts must be removed, cleaned, blown with air, and all internal parts removed. There is a screw in the bottom of the bowl twords the front if I recall correctly, and under it is a steel ball. This must be removed and cleaned as it has something to do with fuel flow at idle. Also the fuel mixture screws on the throttle plate need to be cleaned and checked. You will need to take that thing apart untill you know it like a marine knows his rifle before you can make it stay right. That is why I now run carter afb or edelbrock. It will help you keep your hair, something you will want later in life. Remember to soak it, then blow with air both ways on everything possible.

[GREASEMONKEY72]

i keep my hair really short anyway

and i pretty much do know this thing like a marine and his rifle, ive taken damn near everything off or out and sprayed with carb clean and blown out with air and nothing has fixed it, and i did take out the screw and ball, so i guess i either need a new one or need to see if i can find a place that can dunk it or something, unless theres something else i can do or try

thanks for all the help and im still open to any and all sugguestions

[GREASEMONKEY72]

ttt

[GREASEMONKEY72]

ok i made some progress, the problem is in the top plate of the carb with the hole itself, everything else is fine but the hole that its supossed to squirt out of is whats the problem, its appairently clogged somehow and im trying to see if i can get it cleared but having no such luck so far and im not really sure how to unclog it since its so small but im going to keep trying and ill let yall know if i get or what i end up doing


so for those of you that have the qjets still, check your squirters and make sure nothing gets into the holes

[GREASEMONKEY72]

ok i got it fixed and all it was is that somehow the little hole got plugged up and what saved me was a sewing needle that i used to push through whatever was stuck in the hole and now it works fine

[lbpd719]

good job. When rebuilding carbs, its worth letting them soak in a "boiling" solution of your choice. You can only get so far with spray cans..

[GREASEMONKEY72]

thanks


yea sometimes you have to soak things but i never soaked it, i just kept messing with it and staring at it till i found it, it kicked my ass for a while but i still had fun working on it

[CrashEd]

I find that a torch tip cleaner comes in real handy with things like that. There even nice if you need just a small amont more squirt there like little round files.
Ed

[GREASEMONKEY72]

the torch cleaners would work but mine was stuck pretty good and they would just bend but the sewing pin is stiffer

[eedgell]

Way to go!! Not easy to drill and blast a hole that small!!!! I have used wires off of a good stiff wire brush before, and it got me out of a jam. I know what you mean about it being stuck hard though, and the needle was a good idea. I would still change to a carter style, but each there own. Good luck.